File format matrix

Placemark supports many different geospatial formats. Those formats, in turn, support different features. Geospatial formats vary quite a lot in the features they support. Something like folders might be supported by only one or two formats and not any others. This chart is here to help you understand at a glance what format might be appropriate for your needs.

GeoJSON KML GeoJSONL Polyline CSV Excel TCX GPX FlatGeobuf WKT Shapefile TopoJSON EXIF GeoTIFF
Points
Lines
Polygons
Text Properties
JSON Properties
Folders 1
Styles 2
Import
Export
Encoding Text Text Text Text Text Text Text Text Binary Text Binary Text Binary Binary

Footnotes

  1. TopoJSON supports a very limited idea of a "folder": a feature or group of features can have a shared name which identifies them. For example, a dataset of country, state, and county borders can group the state borders under the name "state" and so on. This is, however, limited: there's no nesting and no additional attributes beyond the name.
  2. There's an additional specification that builds on GeoJSON to add styles: simplestyle-spec. Placemark can export simplestyle-spec encoded styles in GeoJSON, but the GeoJSON format itself doesn't specify how styles can be expressed in GeoJSON. So that one is a mixed answer: you can store styles in GeoJSON, but it's not guaranteed that every place you put that GeoJSON, it'll be styled.

Recommendations

A great default file format is GeoJSON. It's natively supported by map viewers like Mapbox GL, Leaflet, and even the Google Maps API. You can also analyze GeoJSON using desktop tools like QGIS and libraries like Turf.js.

You'll probably encounter a range of file formats, though - KML if you're using Google Earth, GPX and TCX if you're loading data from your GPS tracker, Shapefiles if you're working with legacy GIS systems, WKT if you're interacting often with databases like PostGIS. Placemark happily supports a wide range of geospatial formats, as do many other mapping tools.

Even though they're limited in the kinds of geometries they can reliably represent, CSV and Excel (XLS) tend to be very useful for collaborating with large groups with varied technical experience, because you can edit these formats in spreadsheet tools like Google Docs and Excel.

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